The four Japanese students had four steaks, fried fish, and mineral water at Osteria da Luca.

They paid the bill but complained to police in Bologna.

Venice's mayor pledged to look into the case.

The mayor of Venice has pledged to intervene in a "shameful episode" in which four tourists said they were charged $1,350 (€1,100/£970) for four steaks, fried mixed fish, and mineral water at a local restaurant.

The four Japanese men had been dining at Osteria da Luca near St Mark's Square last Friday when they were presented with the massive bill, The Daily Telegraph reported.

They paid, but complained about it to police upon returning to Bologna, where they were studying, the BBC reported.

Venetian Mayor Luigi Brugnaro tweeted on Sunday: "We will thoroughly examine this episode over the coming days. We'll make sure the complaint was justified.

"If this shameful episode is confirmed, we'll do all we can to punish those responsible. We are for justice, always!"

A spokesman for Osteria da Luca said he had "no recollection of any problems with Japanese customers," The Guardian reported, citing local news sources.

Earlier that evening, three women in the same tour group suspected they were getting ripped off and went to another restaurant, where they were charged €350 for seafood pasta, Marco Gasparinetti, a spokesman for local civic group Gruppo 25 Aprile, told Italy's Ansa news agency.

Osteria da Luca, which Ansa says is managed by an Egyptian and owned by Chinese investors, appears already to be notorious for its exorbitant prices and lacking service.